It is known to manufacture fluoroaromatics by diazotizing an aromatic amine, such as aniline, in anhydrous HF, usually at 0.degree. C., followed by thermal decomposition of the aryldiazonium fluoride. Osswald et al., German Pat. No. 600,706, disclose a two-step process in which sodium nitrite is added to a cold solution of the aromatic amine in anhydrous HF. The reaction mixture is then heated to decompose the diazonium fluoride to give nitrogen and the aromatic fluoride. Misaki et al. in Japanese Patent Publication No. 81330/74, disclose a one-step process wherein the diazotization agent, such as sodium nitrite, in anhydrous HF is fed to a solution of the aromatic amine in anhydrous HF at a sufficiently high temperature (30.degree.-50.degree. C.) that diazotization and decomposition of the diazonium fluoride occur simultaneously. The reaction mass is then cooled, the organic layer allowed to separate and the product isolated by steam distillation. In U.S. Pat. No. 4,075,252, Boudakian claims enhanced yields when ammonium ions are present in the reaction medium, and in U.S. Pat. No. 4,096,196, claims enhanced yields when selected tertiary amines are present. Following the reaction, the reaction mass is cooled, the phases separated, the organic phase neutralized with caustic and the crude fluoroaromatic product steam-distilled. Either of these concepts can be practiced using the one- or two-step processes described above.